Vacuum vessel sealing



Nov. 20, 1928.

H. M BADGER VACUUM VESSEL SEALING Filed Feb. 12, 1925 INVENTOR Harry /7 Badger:

ATTORNEY)" Patented Nov. 20, 1928.

UNITED s'm'rss HARRY M. BADGER, OF GREAT BARRINGTON, MASSACHUSETTS, ASSIGNOR STANLEY 1,591,912 PATENT oFF'IeE.

INSULATING COMPANY, or BERKSHIRE, MASSACHUSETTS, a CORPORATION OF.

MAINE.

VACUUM VESSEL SEALING.

Application filed February 12,1925. Serial No. 8,703.

My invention relates to vacuum bottles and other containers, and to a method of making the same. The invention relates more particularly to containers of the all metal type;

6 having inner and outer walls or shells of sheet metal which are spaced apart, with the space between the shells filled with a suitablegranular insulating material, the air and gases being exhausted from the space between the shells after the insulating material has been placed therein.

Her'etofore in sealing such chambers after exhausting the air and gases, it has been customary to close by solder the end of a lead tube leading from an aperture inthe outer wall of the container, after the air and gases havebeen exhausted through the tube by means of a suitable exhausting apparatus. It has been found, however that when a lead tube is thus employed, it is not possible to heat the container to a sufficiently high temperatureto permit the occluded gases inthe walls of the container to be effectively removed during the exhausting operation provide a sealed container of the character indicated having provision of means for use in sealing the same after exhausting the-air and gases from: the space between the walls of the container which is so constructed as to permit the container to be heated to the required degree during the exhausting operation: to produce the best results;

The several features of the inventionwhereby the: above mentioned and other objects maybe attained will be-clearly understood fromv the following description and accompanying drawings, in which,

Figure 1 is a vertical. sectional view showing. the lower portion of a vacuunr bottle of the all-metal type embodying my invention;

Fig; 2- is a section on the line 2 2, Fig. 1, with certain parts broken away;

Figs. 3 and 4 are vertical sections of other embodiments of my invention.

The vacuum bottle as illustrated in the drawings, is provided with an inner Shell 2 and an outer shell 4 which are spaced apart. The inner shell is provided with a closed bottom 6, and the outer shell is provided with a bottom 8 having a flange 10 that telescopes over and is welded or otherwise" secured to the lower end of the outer shell.

In accordance with my invention the bottle Ehe object of the present invention is tois further provided with a false bottom'12 having: a depending flange 14 [which is re ceived in and is welded to the lower end of the outer shell. baffle 16 is also providedwhichconsists of a sheet metal disk spaced a slight distance above the false bottom 12', and provided with an upwardly rolled mar ginal bead 18 and a depending flange'QO',

The depending flange 20 tightly fits the outer shell, and the baffle is tightly held between. an inwardly rolled bead 22 011 the outerv she'll and'th'e false bottom 1 2'. The bafile 16 is,

provided with a series of slits or cuts 24 which are so fine as to prevent the granular insulat ing material within the space between the shells of the container from passing there through but permitting air and gases to freely pass during the exhausting operation,

Each twoadjacent cuts or slits 24; are formed by punching downwardly a portion of the" metal to separate it and then forcing it back- Thebafiie thus formed is substantially homogeneous, the

to its original position.

faces of theslits being of the same metal as the body of the sheet;

The false bottom '12 is provided with an inwardly tapering conical air exhaust opening or port 26. In the embodiment of F i'gsjj 1 and 2 this port is providedby forminga downwardly extending tubular projection 28,;

the projection tapering inwardlyand being integral with the disk-like portion 12.1 X

sleeve or tube 30 of steel, which may beformed on a screw machine, surrounds the tubular projection and is provided with a flange '32 that engages the under sideof the falsebottom and is electrically welded thereto. The lower end portion of the tube 30 is provided with external screw threads 34. The flange '32 has an external face forming a seat'for an exhaust coupling not shown).

' The screw-threaded en'd 34'of the sleeve or 1 perfectly homogeneous, there being pipes,

' due to traces'of slag and other imperfections through which molecules of gas and air can quite freely pass. As the piece is heated the gas contained in the minute pipes will expand and open the metalwhich make a free passage for ,air and other gases. In the construction above described, however, the grain of the metal of the tubular projection 28 sur rounding the plug'3.6, is: parallel to the surg I fa'cethereof instead of being cross-grained,

and'with such a construction there is not the danger. ofserious trouble in the form of leaks,

In the modified form of container shown 7 in Fig. 3 the exhaust opening extends through anexliaust tubeAS having a laterally extending flange 50 at its upper end which in turn is provided with a depending peripheral flange 52, the lower end of the tube 48 being provided with external screw threads c0rresponding to the screw threads 34 of the form shown in Figs. 1' and 2. The exhaust tube 48 is inserted in an openinginthe false bottom' of the container havinga depending flange 54, the exhaust tube being secured to thefalse bottom by electrically welding the flanges 52 and 54. V The port is closed; by a hermetically sealed metal plug as in Fig. 2.

Inthe modified form shown .in Fig. 4, the exhaust opening extends through a steel tube et2lwhichis provided with a flange 44 engag ing theunder side of'the false bottom, and an annular. upward projection46 which fits into an aperture in the false bottom, the

flange 44 of the exhausttube 42 being electrically welded to the false bottom. The forms shown in Figs. 3 and 4, while more liable to leakagebecause of piping, have advantages in manufacturei With theseconstructions, it will be apparent that during the exhausting operation the walls of the container may be heated to a much higher temperature than though the air and gases were exhausted through a lead tube as has heretofore been customary, thus insuring an effective elimination of the oceluded gases in the metal of the walls of the container. r 7 I In exhausting and sealing'the vessel the same is heated to above the melting point of lead, preferably to about eight hundred degrees Fahrenheit (800 and while so heated the'air is exhausted therefrom by suitable exhausting and plug insertingf neans connected to the exhaust part. The plug is then inserted and forced intoposition by pressure While the vacuum is retained and subsequently, as soon asthe exhausting apparatus is disconnected, hermetically sealed, preferably with solder. In this Waya high vacuum is secured and maintained within the vacuum chamber.

As will be evident to those skilled in the art, my invention permits of various modifications without departing from the spirit thereof or the scope of the appended claims.

What I claim is: r 1. A circular baflie metallic vacuum vessel having an outer shell, a granular filling and anexhaust port,con-

sisting of a sheetof metal located adjacentto said exhaust port and engaging theinterior surface of the wall of the outer shell of the vessel and having a plurality of slits with contacting edges permitting air topass plate fora cylindrical;

but preventing the passage. of the granular material, the faces of-the slits being of the,

same metal as the body portion. of the. plate;

2. A circular baffleplate fora cylindrical.

metallic vacuum vessel havingan outer shell,

a granular filling and an exhaust-port, consisting of a sheet of metal located adjacent to said exhaust port and'engaging-theinterior surface of the wall of the-outer shell of the vessel and having a plurality of slits with contacting edges permitting air to pass:

but preventing the passageof the granular material, saidv slits being arranged in pairs, the slits of each pair being parallel, the faces of the slits being of the same metalas the body portion of the plate. y

In testimony whereof, I'have signed my name to this specification this 9th "dayoff February, 1925. r HARRY M. BADGER. 

